You can purchase a recharge kit from your local auto parts store. It will include directions as to recharging your system. If your system is low or empty on charge you probably have a leak in the system and it will empty soon if you refill it again.
A 1998 Ford Explorer uses refrigerant 134a
R-134a ( I believe since the 1994 Ford Explorer model year )
R - 134a
Buy a kit at Wal-Mart or auto parts comes with instructions
134a refrigerant
134a refrigerant
134a
R-134a
R-134a
AnswerAccording to the Ford/Motorcraft refrigerant capacities data sheet, 1998-2002 Mercury/Ford Cougars have a total R-134a refrigerant capacity of 26 ounces.
It uses R-134a. There's a sticker under your hood in the engine compartment that tells you this and how much.
Should be R-134a